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HM Digital Pocket-Sized TDS Meter w/ Thermometer
Information

The world’s smallest and lightest TDS meter also comes with a built-in digital thermometer. It is a true pocket size meter, comfortably fitting into a shirt pocket without adding bulk. The TDS-4TM-A comes in an aquarium-specific retail-ready packaging.

HM Digital, Inc.Established in 1987, HM Digital, Inc. (formerly known as Heemang Electronics) is an original equipment manufacturer (OEM) that has been recognized worldwide for providing the best values in water testing instrumentation, especially the increasingly popular TDS meter.

HM Digital Pocket-Sized TDS Meter w/ Thermometer
Reviews

Does the job

by
BRIAN FRITZEL

Great

Posted: 6/27/2015 from Chula Vista, CA UNITED STATES

4.05

Experience Level:
Intermediate

Comments:Not much to review four stars out of five just because it Celsius not Fahrenheit be nice if you could switch back-and-forth will besides that works as well is it supposed to come calibrated one day delivery as usual as well good product.

Pre-Calibrated, Great Meter

by
JPowell

Excellent!

Posted: 4/8/2012 from TN UNITED STATES

4.55

Experience Level:
Expert

Comments:Giving this one 4.5 stars only because the cap is a bit loose. It has a clip on it if you wanted to carry it around, but it would fall off very easily. The meter comes pre-calibrated and works right out of the package. Reads TDS almost instantly and seems to be very accurate. Can't beat it for the price.

Must Have!

by
Burto

Great

Posted: 8/31/2011 from TULSA, OK UNITED STATES

4.05

Experience Level:
Intermediate

Comments:Very handy meter. Alerted me the first day to a potential problem with my top off water. I checked the source (city tap) water against my RO and then my RO/DI. My RO/DI was zero but the water in the bottom of my top off reservoir was way high. Now I've covered my reservoir and the levels back down to near zero. Disaster averted.
Would have given 5 stars except for the temp feature is in celcius.

Readings in Celsius only

by
JIM BENGE

Below Average

Posted: 8/30/2011 from LIVERMORE, CA UNITED STATES

2.05

Experience Level:
Intermediate

Comments:Note that this product will *not* display temp in Fairenheit
Also, I could not get a TDS reading on the saltwater in my tank, it would just display dashes; however, it would give me readings on freshwater.
Great price, but being in the U.S., I'm used to temps in Fairenheit.

HM digital TDS meter

by
Troy

Excellent!

Posted: 4/1/2011 from PETALUMA, CA UNITED STATES

5.05

Experience Level:
Intermediate

Comments:Works great, simple and easy.
Popped it in some "RO" water I had purchased the day before and it spat out 175ppm, not buying there again (my tap water is 256ppm btw).
As a control, I tested it on distilled and it read 000ppm.
The temp feature seems accurate as well, in reality I don't have much use for the feature. I have only tested it once and it was spot on.